The present invention, in some embodiments thereof, relates to a surface and a method for displaying images and, more particularly, but not exclusively, to a surface and a method for displaying interlaced images.
Conventional print advertising, decorating, branding, and packaging is usually accomplished by printing stationary non-moveable information and pictures on two or three dimensional objects. One of the primary purposes of the printing is to attract the attention of observers. In an effort to attract the customer's attention, various types of displays have been developed. Examples for conventional displays are illuminated signs, including neon signs, billboard illuminated with flood lights and spot lights, marquees with moving messages, blinking lights, and the like. Other displays such as angle dependent displays have also been developed. Examples for angle dependent displays are directional display sheets, such as lenticular lens and barrier sheets. From the observer point of view, an angle dependent display displays an image that changes when viewed from different angles. Integral viewing sheets include an interlaced image that combines strips of at least two images and an optical barrier, such as an array of lenticular lenses and a parallax barrier. The optical barrier allows the creation of a dynamic image, for example by offsetting the various layers of the interlaced images at different increments in order to give a motion effect and/or a three dimension (3D) effect to the observer. The most common method of printing lenticular images, which accounts for the vast majority of lenticular images in the world today, is lithographic printing of the composite interlaced image directly onto flat surface of the lenticular lens sheet. From the observer point of view a conventional display displays the same dynamic image regardless to the distance thereto and an angle dependent display, when designed to display distinctly different images, displays a distinct image only when the observer is in a limited domain of viewing distance therefrom.
For example, U.S. Pat. No. 5,494,445, filed on Oct. 31, 1994, depicts an efficient economical process is provided to produce an intricate impressive display with outstanding marketing and advertising appeal. In the process, multiple images are formed, such as on a central processing unit, the images are masked and striped, and portions thereof are superimposed. The superimposed masked images can be printed on an underlying back rearward web. Transparent rods, a plate lens, lenticular lens, a cluster of anomorphic lenses, or a grid, can be placed front of the back web to provide a special display which has the illusion of animation as the angle of sight changes.
It should be noted that using a parallax barrier for creating integral viewing sheets results a great deal of light which is absorbed and/or diffused by it. Thus, such integral viewing sheets may suffer from a decreased brightness problem. Solutions for increasing the brightness of such integral viewing sheets have been developed. For example, a backlight element, which is attached to the back of an integral viewing sheet, is designed function as an alternative light source that replaces the light that is absorbed and/or diffused by the parallax barrier. In another solution, the absorbed light is reuse. The light absorbed or diffused by barrier is guided back to a reflected layer to create backlight that raises the illumination in approximately 114.47%, see Chien-Yue Chen et. al., a novel high brightness parallax barrier stereoscopy technology using a reflective crown grating, National Yunlin University of Science and Technology, Taiwan, Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1610-1616, 2008, which the content thereof is incorporated herein by reference.